1. Field of the Invention
2. Description of the Prior Art
This invention relates to non-allergenic lanolin and derivatives thereof, and to a process for producing the same.
Lanolin is a higher fatty acid ester with a higher alcohol or sterol. The main fatty acid component includes the normal-, iso- and anteiso-isomer of an alkane acid,and an .alpha.- and W-hydroxy acid, and therefore has a total of nine chemical forms. On the other hand, the alcohol component includes six varieties chemical forms which are normal-, iso- and anteiso-isomer of a mono-alcohol and a .alpha., .beta.-diol, and several kinds of sterols.
It has been postulated that lanolin is a combination of the above alchols and acids, or a polymerized product thereof, in addition it contains several percent of substances, the structures of which remain unknown. Thus, lanolin is distinguished by the fact that is has no main component, but does have a sterol content of about 30% which corresponds to the major component.
Hitherto, lanolin has been widely used as a base for drug ointments and as a base for cosmetic creams and lotions however, it has very often induced an allergy at an occurrence frequency ranging from 1 to 18% in subjects.
It has been reported that the lanolin-induced allergy was observed with the same or more frequency as found with allergens such as nickel, chromium, p-phenylenediamine and the like, but less frequently observed than with formaldehyde.
Concerning the lanolin-induced allergy, Marcus at first reported some results with the use of a lanolin alcohol-combined cream as a test compound in 1922, but he did not refer at all to what really acted as the allergen in the test compound.
Thereafter, Sezary carried out many experiments with lanolin in 1936, but he could not find any components of lanolin capable of acting as an allergen, because of its highly complicated chemical structure, and merely cited a general term of lanolin compound as an allergen.
Fanburg first estimated lanolin alcohol to be an allergen in 1940. Subsequently, many investigators made a large number of studies on lanolin, lanolin alcohol and lanolin derivatives over a period of 30 years. Notwithstanding their continued efforts, the substance acting as the allergen still remains unknown. This is due to the difficulty of judgment of the allergy tests and the complicated chemical composition of lanolin.